Astronomers have identified a distant exoplanet, WASP-127b, boasting winds that reach mind-blowing speeds of approximately 5.6 miles (9 kilometers) per second, or more than 20,500 miles per hour (33,000 km/h). These ferocious gusts are faster than any planetary winds documented in the known universe, surpassing even the intense wind speeds observed on the outer planets of our own solar system.
A “Puffy” Gas Giant Revealed
Originally discovered in 2016, WASP-127b lies roughly 520 light-years away from Earth. It is slightly larger than Jupiter yet contains only 16% of Jupiter’s mass, making it one of the least dense (or “puffiest”) exoplanets on record. This low density allows astronomers to investigate its upper atmospheric layers much more easily than those of denser gas giants.
The exoplanet completes an orbit around its host star in just four days on a slightly skewed trajectory and is likely tidally locked, similar to how the Moon always shows the same face to Earth. This means one side of WASP-127b is perpetually in daylight, while the other side remains in permanent darkness.
Spectroscopic Clues from the Very Large Telescope
A research team led by Lisa Nortmann at Germany’s University of Göttingen conducted observations of WASP-127b with the European Southern Observatory’s Very Large Telescope (VLT) in Chile. As the exoplanet passed in front of its star, it partially blocked the star’s light. By analyzing this filtered starlight—especially its unique molecular “fingerprints”—the scientists found carbon monoxide and water vapor in the planet’s upper atmosphere.
Surprising Signals, Supersonic Winds
While examining these molecular signatures, the researchers noted an unusual dual pattern in the data: one indicating that some atmospheric molecules were shifting toward Earth, and the other suggesting movement away from Earth. This dual signature implied staggeringly fast jet streams circling the planet—likely supersonic winds racing around its equator.
According to the team, these winds move about six times faster than WASP-127b itself rotates. For comparison, Neptune—the windiest planet in our solar system—features wind speeds topping out at around 1,200 miles per hour (1,900 km/h). WASP-127b’s winds, however, are believed to be 18 times stronger, making them the fastest ever detected on a planet.
Changing Temperatures and Complex Weather Patterns
Additional observations revealed temperature variations between the morning and evening sides of WASP-127b, hinting at dynamic weather systems reminiscent of those on Earth. Such temperature contrasts can drive massive, planet-spanning storms and further amplify wind speeds, contributing to the supersonic jet streams detected at the equator.
Significance for Exoplanet Research
These groundbreaking findings, now published in the journal Astronomy & Astrophysics, provide a window into the exotic climates of ultra-light gas giants. WASP-127b’s extremely low density and rapid orbital period make it an ideal candidate for future in-depth atmospheric studies, especially with new and upcoming observatories like the James Webb Space Telescope (JWST) and next-generation ground-based telescopes.